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1.
Horm Metab Res ; 21(5): 272-4, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2789167

RESUMO

We explored a 61 year old woman with mild hirsutism. An adrenal tumor was found in the left adrenal, which was held responsible for the androgen secretion. The in vitro incubation of the tumor tissue showed an impaired 11 beta-hydroxylation of 11-deoxycortisol. This is a rare and unusual case of adrenal pathology showing that a deficiency in 11 beta-hydroxylase activity does not rule out the presence of an adrenocortical adenoma.


Assuntos
Adenoma/enzimologia , Neoplasias do Córtex Suprarrenal/enzimologia , Hiperplasia Suprarrenal Congênita , Esteroide Hidroxilases/deficiência , Adenoma/cirurgia , Neoplasias do Córtex Suprarrenal/cirurgia , Adrenalectomia , Androgênios/sangue , Feminino , Humanos , Cetosteroides/biossíntese , Pessoa de Meia-Idade
2.
Endocrinology ; 123(6): 2906-15, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3197648

RESUMO

Leydig cells atrophy, losing cytoplasmic volume and the capacity for testosterone secretion, within 1-2 weeks of LH deprivation. We investigated the effects of long term (0-16 weeks) LH deprivation on the volume of an average Leydig cell, the volume of Leydig cells per testis, the number of Leydig cells per testis, and testosterone secretion by in vitro perfused testes. Endogenous LH was suppressed in adult rats by testosterone/estradiol-filled (TE) Silastic implants. The presence of Leydig cells in testes was verified by 1) morphological examination using light and electron microscopy, 2) histochemical localization of 3 beta-hydroxysteroid dehydrogenase activity (3 beta HSD), and 3) conversion of pregnenolone to progesterone by in vitro perfused testes. Marked quantitative differences existed in Leydig cell morphology among control and treated rats. The volume of an average Leydig cell and the total volume of Leydig cells per testis decreased (P less than 0.01) rapidly and progressively after TE implantation. At 16 weeks, the average Leydig cell lost 90% of its cytoplasmic volume and 65% of its nuclear volume. Analysis of variance failed to detect a significant decline in Leydig cell number per testis, despite a 16% reduction from the value in control rats (22.2 +/- 1.5 x 10(6)) in rats treated for 16 weeks (18.7 +/- 1.5 x 10(6)). After TE implantation, LH-stimulated testosterone secretion by in vitro perfused testes diminished (P less than 0.01) rapidly to 5% of the control values at 1 week and less than 0.3% of the control value from 4-16 weeks. In contrast, 25% of 3 beta HSD activity was retained (P less than 0.01 vs. controls) at 16 weeks, based on the rate of pregnenolone conversion to progesterone. Moreover, testes of treated rats secreted progesterone at a rate twice that of controls, when the steroid secretion rates were expressed per volume of Leydig cell cytoplasm. Loss of the testosterone-secreting capacity of testes after LH withdrawal was associated with a loss in the volume, but not a significant loss in the number, of Leydig cells. Thus, LH was required to maintain the differentiated structure and function of Leydig cells, but was not required to maintain the overwhelming majority of Leydig cells in the adult rat testis through 16 weeks. Moreover, at least one steroidogenic enzyme, 3 beta HSD, was retained by Leydig cells after long term LH deprivation.


Assuntos
Células Intersticiais do Testículo/ultraestrutura , Hormônio Luteinizante/fisiologia , Testículo/metabolismo , Testosterona/biossíntese , 3-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Contagem de Células , Núcleo Celular/ultraestrutura , Citoplasma/ultraestrutura , Estradiol/farmacologia , Histocitoquímica , Cetosteroides/biossíntese , Masculino , Microscopia Eletrônica , Pregnenolona/metabolismo , Progesterona/metabolismo , Ratos , Ratos Endogâmicos , Testículo/citologia , Testículo/efeitos dos fármacos , Testosterona/metabolismo , Testosterona/farmacologia
6.
J Gen Virol ; 66 ( Pt 2): 267-73, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2981969

RESUMO

In addition to its antiviral effect, interferon, at high concentrations, stimulates steroidogenesis and provokes cell rounding in Y-1 mouse adrenal tumour cells. This stimulation was inhibited by cytochalasin B and colchicine. In contrast, dibutyryl cAMP and cholera toxin, also able to induce steroid production and cell rounding, increased steroid production even in the presence of these cytoskeleton-disrupting agents. The initial trigger for interferon or cholera toxin thus probably involves a distinct receptor organization. However, since both inducers increased cAMP synthesis in this differentiated cell line, the further metabolic steps of ketosteroid production could be the same.


Assuntos
Neoplasias das Glândulas Suprarrenais/metabolismo , Butiratos , Toxina da Cólera/farmacologia , Interferon Tipo I/farmacologia , Cetosteroides/biossíntese , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Bucladesina/farmacologia , Linhagem Celular , Colchicina/farmacologia , Citocalasina B/farmacologia , Citoesqueleto/efeitos dos fármacos , Camundongos
7.
J Steroid Biochem ; 20(3): 763-8, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6231429

RESUMO

Trilostane is known as an inhibitor of 3 beta-hydroxysteroid dehydrogenase. Conflicting data published on this drug led us to look for the effects of 0.02 to 0.5 mM of trilostane on the in vitro steroid synthesis in sheep adrenals and human adrenals (Cushing's or Conn's syndrome) in the presence of an NADPH-generating system. The synthesis of 4-androstenedione, 11 beta-hydroxyandrostenedione and 11-ketoandrostenedione were studied either from dehydroepiandrosterone or 4-androstenedione or 11 beta-hydroxyandrostenedione. The synthesis of 11-deoxycortisol, cortisol, cortisone, 4-androstenedione, 11 beta-hydroxyandrostenedione and 11-ketoandrostenedione were studied either from 17-hydroxyprogesterone or 11-deoxycortisol or cortisol. This study showed that trilostane inhibited 3 beta-hydroxysteroid dehydrogenase whereas it had no effect on 21-, 11- and 17-hydroxylase. Trilostane was responsible for an increased 11 beta-hydroxysteroid dehydrogenase activity in vitro, resulting in low yields of cortisol and 11 beta-hydroxyandrostenedione, and high yields of cortisone and 11-ketoandrostenedione. This unexpected effect of trilostane allowed us to show that erroneous conclusions (in this case: pseudo inhibition of 11 beta-hydroxylase) can be drawn if all the metabolic pathways from a determined precursor are not exhaustively documented when studying the effects of drugs on steroid synthesis in vitro. The decrease of cortisol synthesis by trilostane may thus be related to the effects of the drug on both 3 beta-hydroxysteroid-dehydrogenase (inhibitory effect) and 11 beta-hydroxysteroid-dehydrogenase (stimulatory effect). This latter effect was found to be species-dependent.


Assuntos
Glândulas Suprarrenais/enzimologia , Androgênios/biossíntese , Di-Hidrotestosterona/análogos & derivados , Hidroxiesteroide Desidrogenases/metabolismo , Hidroxiesteroides/biossíntese , Cetosteroides/biossíntese , 11-beta-Hidroxiesteroide Desidrogenases , 3-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , Glândulas Suprarrenais/efeitos dos fármacos , Androstenodiona/metabolismo , Animais , Desidroepiandrosterona/metabolismo , Di-Hidrotestosterona/farmacologia , Humanos , Ovinos , Especificidade da Espécie
8.
Steroids ; 40(5): 591-601, 1982 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6226130

RESUMO

3 beta-Hydroxy-5-androsten-17-one is converted to 5-androstene-3, 17-dione by rat liver alcohol dehydrogenase (ADH). We have reported on the purity of the enzyme which is eluted with pyrazole as a single homogeneous protein using an AMP-agarose affinity column. Rat liver ADH can oxidize hydroxyl groups not only at 3 beta-, but also at 3 alpha-, and 17 beta-positions to a lesser extent; thus it is a pure mammalian enzyme with multifunctional activity for steroids. Since it does not contain delta 5-isomerase activity, the reaction of the dehydrogenase to form the delta 5-ketosteroid intermediate can be observed at pH 7.0, 25 degrees C. Similarly, intermediary product, 5-pregnene-3,20-dione, can be isolated in the conversion of pregnenolone by ADH to progesterone. With buffer alone in a cuvette, a non-enzymatic isomerization of the delta 5-3-ketone occurs at a slow rate (t 1/2 = 6 hrs) but occurs rapidly during isolation procedures. The delta 5-3-ketosteroid intermediates were identified by their behavior on TLC plates with UV light and by their characteristic spectra in the NMR.


Assuntos
Oxirredutases do Álcool/metabolismo , Cetosteroides/biossíntese , Fígado/enzimologia , Álcool Desidrogenase , Oxirredutases do Álcool/isolamento & purificação , Animais , Desidroepiandrosterona/metabolismo , Cetosteroides/isolamento & purificação , Cinética , Espectroscopia de Ressonância Magnética , Oxirredução , Pregnenolona/metabolismo , Ratos
9.
J Clin Endocrinol Metab ; 53(2): 401-5, 1981 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6265490

RESUMO

Preparations of dispersed human fetal adrenal cells from the inner third of the gland and from the subcapsular area were maintained in culture, and their ultrastructure and steroid production were studied. The former type of preparation contained only fetal zone cells, while the latter contained definitive zone cells together with varying numbers of fetal zone cells. Both types could be cultured with equal ease, but during short term culture, fetal and definitive zone cells became morphologically indistinguishable. The patterns of steroid production and, in particular, the relative production of delta 4,3-ketosteroids and delta 5,3 beta-hydroxysteroids were similar in both preparations, as were their dose-response relationships during incubation with alpha ACTH-(1-24). Although considerable variability in total steroid production was observed between cells from different adrenal glands, in no specimen was any evidence for functional zonation of the fetal adrenal cortex observed in vitro. The results suggest that the apparently unique histological appearance and function of the fetal adrenal cortex may only reflect intense stimulation by ACTH secondary to the combined influences of a rapid cortisol MCR and of some inhibitor of fetal adrenal 3 beta-hydroxysteroid dehydrogenase activity.


Assuntos
Córtex Suprarrenal/metabolismo , Glândulas Suprarrenais/embriologia , Hidroxiesteroides/biossíntese , Cetosteroides/biossíntese , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/metabolismo , Glândulas Suprarrenais/ultraestrutura , Hormônio Adrenocorticotrópico/farmacologia , Células Cultivadas , Desidroepiandrosterona/biossíntese , Humanos , Hidrocortisona/biossíntese , Microscopia Eletrônica
11.
J Gen Virol ; 50(2): 447-50, 1980 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6161994

RESUMO

Interferon, like cholera toxin, induces in mouse adrenal YI cells the production of delta 3(4) ketosteroids. In parallel, cyclic AMP (cAMP) is activated. At high concentrations, mouse but not human interferon induces a cell rounding effect, similar to that obtained with cholera toxin. In YI cells transformed by simian adenovirus 7, production of cAMP is still increased by that of steroids is blocked. The role if interferon in these cellular events is discussed.


Assuntos
Interferons/farmacologia , Cetosteroides/biossíntese , Adenoviridae/fisiologia , Neoplasias das Glândulas Suprarrenais , Animais , Linhagem Celular , Transformação Celular Viral , AMP Cíclico/metabolismo , Camundongos , Vírus da Estomatite Vesicular Indiana/crescimento & desenvolvimento
14.
Infect Immun ; 13(5): 1479-82, 1976 May.
Artigo em Inglês | MEDLINE | ID: mdl-1270152

RESUMO

A purified subunit of the cholera enterotoxin molecule was found to have morphological and steroidogenic inducing effects similar to those induced by the native enterotoxin on monolayer tissue cultures of Y1 adrenal tumor cells, although 1,000 times more subunit than toxin (weight basis) was required for maximal effects. In contrast to the whole toxin, the effects of the active subunit could not be prevented by prior incubation with either Gm1 ganglioside or with antibodies directed against choleragenoid (the binding subunit). These results suggest that different receptor sites may exist on cells for the binding and for the active subunits of cholera enterotoxin and/or that the active toxin fragment may exert its effects after gaining access to the intracellular compartment.


Assuntos
Transformação Celular Neoplásica/patologia , Enterotoxinas/farmacologia , Cetosteroides/biossíntese , Neoplasias Experimentais/imunologia , Vibrio cholerae/imunologia , Anticorpos Antibacterianos , Células Cultivadas , Gangliosídeos/farmacologia , Neoplasias Experimentais/análise
15.
Endocrinology ; 98(3): 571-9, 1976 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1261488

RESUMO

Ovarian homogenates from 10-150-day-old rats were incubated with [3H]progesterone and NADPH. Also, ovarian homogenates from 28-day-old rats were incubated for 5-180 min with either [14C]progesterone, [3H]5alpha-pregnane-3,20-dione or [14C]progesterone plus [3H]5alpha-pregnane-3,20-dione. Following incubation, radioactive metabolites were isolated, identified, and measured by column and paper chromatography, with derivative formation and recrystallizations to constant specific activity. Prepubertal ovaries (10, 20, and 28 days of age) converted 15-60% of progesterone to C21-17-hydroxysteroids and C19-steroids. At 40 and 150 days of age (postpubertal), the formation of these steroids decreased to less than 2%. At 10 and 150 days of age, the major C19-steroids formed from progesterone were androstenedione and testosterone. At 20 and 28 days of age, however, no accumulation of these C19-delta4-3ketosteroids was found (less than 0.1% of each), at which time the conversion of progesterone to 5alpha-reduced C19-steriods, such as androsterone and 5alpha-androstane-3alpha,17beta-diol, reached 30%. In ovaries of 28-day-old rats, the results from incubation studies for the detection of metabolic pathways indicated two biosynthetic pathways leading to 5alpha-reduced C19-steroids, one from progesterone via 5alpha-reduced C21 steroids, such as 3alpha-hydroxy-5alpha-pregnan-20-one and 3alpha,17alpha-dihydroxy-5alpha-pregnan-20-one, and a second via 17-hydroxyprogesterone, androstenedione, and testosterone. It seems that the active 5alpha-reduction of C19-delta4-3-ketosteroids and the formation of 5alpha-reduced C19-steroids by the pathway through 5alpha-reduced C21-steroids, are present in the ovaries of older prepubertal rats and may be the biological significance.


Assuntos
Androgênios/biossíntese , Ovário/metabolismo , Progesterona/metabolismo , Androstanos/biossíntese , Androstenodiona/biossíntese , Androsterona/biossíntese , Animais , Feminino , Hidroxiesteroides/biossíntese , Cetosteroides/biossíntese , Pregnanodionas/metabolismo , Ratos , Testosterona/biossíntese
16.
Biochem J ; 152(3): 433-43, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-776170

RESUMO

Treatment of pregnant rats with human chorionic gonadotrophin, luteotrophin (luteinizing hormone), luteotrophin-releasing hormone, prostaglandin F2alpha, aminoglutethimide, or by foetoplacental removal or hysterectomy achieved a common multiple-response pattern, namely increased activity of luteal 20alpha-hydroxy steroid dehydrogenase with decreased activity of delta5-3beta-hydroxy steriod dehydrogenase and release of delta4-3-oxo steroids in vitro. 2. Similar effects of foetoplacental removal are noted in pregnant mice. 3. Gonadotrophin induced lower activities of 20alpha-hydroxy steroid dehydrogenase, except at the very end of pregnancy, and partly inhibited the induction caused by foetoplacental removal. 4. The results suggest that existence of a placental factor that restrains these changes until the end of normal pregnancy, which is produced in amounts proportional to the number of placentae and is conveyed to the ovary via the blood. 5. This factor was not replaced by prolactin. 6. It is argued that neither placental lactogen nor pituitary luteotrophin participate in the induction of 20alpha-hydroxy steroid dehydrogenase at late pregnancy in the rat. 7. Aminoglutethimide induced 20alpha-hydroxy steroid dehydrogenase only in late pregnancy. This was partly reversed by progesterone, wholly reversed by progesterone plus oestrogen, and did not involve the pituitary.


Assuntos
Corpo Lúteo/enzimologia , Aminoglutetimida/farmacologia , Animais , Gonadotropina Coriônica/farmacologia , Corpo Lúteo/efeitos dos fármacos , Estrogênios/farmacologia , Feminino , Feto/metabolismo , Hormônio Liberador de Gonadotropina/farmacologia , Hidroxiesteroide Desidrogenases/metabolismo , Histerectomia , Cetosteroides/biossíntese , Lactose/biossíntese , Hormônio Luteinizante/farmacologia , Camundongos , Ovário/efeitos dos fármacos , Ovário/enzimologia , Placenta/metabolismo , Lactogênio Placentário/fisiologia , Gravidez , Progesterona/farmacologia , Prostaglandinas F/farmacologia , Ratos , Fatores de Tempo
17.
Biochem J ; 152(3): 445-8, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1227499

RESUMO

Natural or early weaning of rat litters caused an increased activity of maternal luteal 20alpha-hydroxy steroid dehydrogenase and a decreased release of delta4-3-oxo steroids in vitro. 2. Compound CB-154 (2-bromo-alpha-ergocryptine) caused an increase of 20alpha-hydroxy steroid dehydrogenase activity in mid-lactation but not in early lactation. 3. Prolaction did not prevent these increases in enzyme activity.


PIP: Luteal 20alpha-hydroxysteroid dehydrogenase and the formation of delta-4-3-oxo steroids after weaning, and treatment with 2-bromo-alpha-ergocryptine during lactation were investigated in the rat. Maternal luteal 20alpha-hydroxy steroid dehydrogenase activity on Day 10 of lactation was greatly increased when the litter had been removed 0-3 days before. In contrast, a decrease in the release of delta-4-3 oxo steroids in vitro was seen with early removal of the litter. The increase in 20alpha-hydroxy steroid dehydrogenase activity due to litter removal was not prevented by the simultaneous injection of prolactin. 2-broma-alpha-ergocryptine caused an increase of 20alpha-hydroxysteroid dehydrogenase activity in midlactation but not in early lactation. Prolactin did not prevent the increase. It is suggested that luteotrophin could possibly account for the enzyme induction after weaning.


Assuntos
Bromocriptina/farmacologia , Ergolinas/farmacologia , Lactação/efeitos dos fármacos , Adrenalectomia , Animais , Corpo Lúteo/enzimologia , Feminino , Hidroxiesteroide Desidrogenases/metabolismo , Cetosteroides/biossíntese , Ovário/efeitos dos fármacos , Gravidez , Prolactina/farmacologia , Ratos , Fatores de Tempo , Desmame
20.
Environ Physiol Biochem ; 5(6): 428-39, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1213032

RESUMO

Tissue from a harp seal given methyl mercury at a concentration of 0.25 mg/kg in its diet for 61 days, was highly contaminated with mercury. Over 70% of the mercury in the seal's liver (64.0 p.p.m.) was in the inorganic form indicating a demethylating system in this organ. Most of the mercury in the liver, spleen and kidney of an untreated seal was also in the inorganic form. In contrast, over 75% of the mercury in the adrenals and gonads (14.2 and 13.0 p.p.m., respectively) of the treated seal was methyl mercury. Mercury was not detectable in the gonads and not analyzed in the adrenals of the untreated seal. Biosynthesized (in vitro) cortisol, corticosterone, cortisone, and 11-ketotestosterone were isolated and identified from the adrenal incubations, and delta4-androstene-3,17-dione and testosterone were isolated and identified from ovarian incubations from both untreated and methyl mercury (in vivo) treated seals. The ovaries and adrenals from both seals appeared to be normal under the light microscope. The ovaries from both seals were in the same follicular phase, but in vitro incubations of tissue from these organs indicated that the methyl mercury and treatment caused a marked alteration of steroid biosynthesis in tissue from the treated seal. The altered pattern of steroid biosynthesis was also demonstrated by autoradiography, and it is suggested that this technique could be used as an indicator of incipient contamination by a pollutant.


Assuntos
Caniformia/metabolismo , Compostos de Metilmercúrio/toxicidade , Focas Verdadeiras/metabolismo , Esteroides/biossíntese , Poluentes Químicos da Água/toxicidade , Poluentes da Água/toxicidade , Glândulas Suprarrenais/metabolismo , Androstenodiona/biossíntese , Animais , Corticosterona/biossíntese , Cortisona/biossíntese , Feminino , Hidrocortisona/biossíntese , Cetosteroides/biossíntese , Rim/metabolismo , Fígado/metabolismo , Masculino , Mercúrio/metabolismo , Intoxicação por Mercúrio/metabolismo , Ovário/metabolismo , Baço/metabolismo , Testosterona/biossíntese
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